1. Field of the Invention
This invention relates generally to the control of autonomous vehicles and, more particularly, to a system and method for remotely controlling an autonomous vehicle.
2. Related Art
Caterpillar Inc. of Peoria, Ill., manufactures off-road mining vehicles. For example, the Caterpillar 777C is an off-road mining truck. Commonly owned, allowed U.S. Pat. No. 5,390,125, filed Feb. 18, 1993, "Vehicle Position Determination System and Method," the full text of which is incorporated herein by reference, discloses an autonomous vehicle system for use with a mining vehicle such as the 777C truck.
Commonly owned U.S. patent application Ser. No. 08/299,447, filed on even date herewith, and titled "System for Controlling a Vehicle to Selectively Allow Operation in Either an Autonomous Mode or a Manual Mode," discloses a system for selectively operating an autonomous vehicle in an autonomous mode or manual (i.e., manned) mode.
At times it may be desirable to provide remote-control or tele-control mode for the vehicle. In tele-operation, an operator could control the vehicle using a tele-panel or remote control which communicates commands to the vehicle via radio waves. This mode might be used, for example, by a mechanic to position the vehicle within a service bay. This mode might also be used by a foreman on a job site to temporarily take control of an autonomous vehicle to route it around an obstacle.
To ensure safety, the transition periods between autonomous, manual and tele-operation must be strictly controlled. Moreover, the status (i.e., who is in control) of the vehicle must always be known.